Describe the structure and function of the major organic
molecules found in living systems:

carbohydrates

proteins

enzymes

lipids

nucleic acids
Carbohydrate - an organic molecule with the formula of Cn(H2O)n.
Its main function is as an energy source.
Lipid -an organic molecule whose main function is energy storage.
Nucleic acid - an organic molecule whose main function is to store
and transmit genetic information.
Nucleotide - monomer/building block of nucleic acids.
Protein - an organic molecule whose main functions are building
body structures, speeding up chemical reactions, and fighting
diseases.
Amino acid - monomer of proteins.
• When you are done, compare your list with
others at your table.
- Make a list with your friends, have one student write it
down.
• Compounds that contain (have) carbon.
• Most biological molecules are organic compounds.
Four organic molecules make up all of the life on Earth. Organic
molecules contain carbon and hydrogen chemically linked to one
another in long chains, with carbon as the backbone and hydrogen
atoms attached to the carbon atoms. These atoms' ability to attach to
one another allows for the creation of innumerable compounds
conducive to life.
All organisms need four types of organic molecules: nucleic acids,
proteins, carbohydrates and lipids; life cannot exist if any of these
molecules are missing.
A) Carbohydrate
B) Lipid
C) Nucleic acid
D) Oxygen
1) Carbon has four valence electrons.
2) Each electron can join with an electron from
another atom to form a strong covalent bond.
3) A carbon atom can bond to another carbon
atom.
- It can make chains, form rings, and single, double and
triple bonds.
- It can form millions of different large and complex
structures.
• Macro = large, big, giant.
• Molecules made from thousands of smaller molecules.
Macromolecules are made by a process known as:
• Polymerization = smaller molecules joining together to make larger
molecules.
• Monomers = smaller units (molecules).
• Mono = 1
• Polymers = smaller units joined together
• Poly = many
A) The building blocks of polymers
B) Long chains of molecules
C) Macromolecules
D) All of the above
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CARBOHYDRATES
LIPIDS
NUCLEIC ACIDS
PROTEINS
• Chemical composition: carbon, hydrogen, and oxygen in a 1:2:1
ratio.
• Function:
• Main source of energy for living things.
• Immediate energy supply.
• Ex: glucose.
• Plants and some animals also use carbohydrates for structure and support.
• Extra sugars are stored so they can be used later.
• Plants store in the form of starch.
• Animals store in the form of glycogen.
• Stored in the liver
• Monomer: Monosaccharide = single sugar molecule.
• Ex: glucose, galactose (component of milk), fructose (sugar in fruit).
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Is a carbohydrate.
Most important monosaccharide.
Only carbohydrate molecule the brain uses as energy source.
Virtually the only fuel used by the brain except during
prolonged starvation.
• large molecules formed from monosaccharides.
• Ex: glycogen (animals) and starch (plants) to store excess sugar.
• Cellulose fibers that give strength and rigidity to plants.
A) Lipids
B) Proteins
C) Nucleic Acids
D) Carbohydrates
• Chemical composition: mostly carbon and hydrogen atoms, and
oxygen.
• Generally not soluble in water.
• Categories of lipids are: fats, oils, waxes and steroids.
• Function:
• makes up important parts of biological membranes and waterproof
coverings.
• Energy production and storage
• Second energy source (used when carbohydrates are used up).
• Preferred way to store energy in the body.
• Insulation and protection
• Digestion and absorption
• Hormones - Steroids work as chemical messengers.
• Lipids do not make polymers.
• Monomer: Many lipids are formed when a glycerol molecule
combines with compounds called fatty acids.
• Saturated fats have each carbon atom in a lipid’s fatty acid chains
joined to another carbon atom by a single bond. Solid in room
temperature.
• Unsaturated fats have at least one double bond between carbons.
Liquid in room temperature.
• Chemical composition: nitrogen, carbon, hydrogen, and oxygen.
• Monomer: amino acids (smallest protein unit)
• Proteins = multiple amino acid molecules together. They are
polymers of amino acids.
• Amino Acids have an amino group (-NH2) on one end and a
carboxylic group (-COOH) on the other.
A) Fatty Acids
B) Nucleotide
C) Protein
D) Simple Sugar
• Function:
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Makes up bones and muscle.
Control the rate of reactions - Enzymes.
Regulate cell processes.
Transport materials into or out of the cell.
Help fight disease.
Can be used as an energy source after lipids.
• Proteins are one of the most diverse macromolecules.
• There are more than 20 different amino acids found in nature.
• 11 are made in our body.
• 9 we get from foods we eat.
• The R-group determines which amino acid it is.
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Some “R” groups are acidic and some are basic.
Some are polar and some are nonpolar.
Some contain carbon rings.
The instructions for arranging amino acids into many
different proteins are stored in DNA.
A) Fatty acids
B) Amino acids
C) Carbohydrates
D) lipids
• You recently found out your best friend suffers from an eating
disorder called anorexia. She eats very little, and does not
consume enough daily calories. Based on what you have learned,
which order of organic molecules will her body consume and how
will this affect her health?
• Chemical composition: Carbon, Hydrogen, Oxygen, Nitrogen and
Phosphorus (CHONP).
• Nucleic acids are polymers assembled from individual monomers
known as nucleotides.
• Nucleotides = 5-carbon sugar + phosphate group + nitrogenous
base.
• Nucleotides are joined together by covalent bonds to form nucleic acids.
• Function: Nucleic Acids store and transmit hereditary, or genetic
information.
• There are two kinds of nucleic acids:
• Ribonucleic Acid (RNA)
• Contains the sugar ribose.
• Deoxyribonucleic Acid (DNA)
• Contains the sugar deoxyribose.
Carbohydrate
For each macromolecule include:
1) Chemical composition
2) Monomers
3) Examples
4) Function in Living Things
5) Draw the molecule
Lipid
Protein
Nucleic Acid
• Lugol’s (Iodine) solution – tests for starch.
• Dark blue or black if starch is present.
• Benedict’s reagent– tests for glucose.
Amount of
Sugar
0
none
+
Very little
++
little sugar
+++
some sugar
++++
much sugar
Color
Blue
Blue/green
Green
Yellow
Orange/red
• Biuret reagent- tests for proteins.
• Pinkish purple if protein is present.